Structural behaviour of double skin composite system using ultra-lightweight cement composite

• We develop a lightweight double skin composite system (DSCS) using ULCC.
• We provide new test data for ULCC filled double skin beam, shell and walls.
• We evaluate the structural behaviour of lightweight double skin composite system.
• We check the feasibility of current codes for ULCC filled DSCS members.

This paper develops a new type of ultra-lightweight cement composite (ULCC) of density less than 1400 kg/m3 and strength up to 60 MPa for double skin composite construction. The ULCC will be filled into double steel plates to form a new lightweight double skin system. To mobilise the material strength, shear connectors including overlapped headed studs and J–J hooks were introduced for the double skin structure. This paper mainly evaluates the structural performance of the lightweight double skin composite system filled with ULCC. A series of tests have been carried out on double skin composite beams, shells and walls with shear connectors. From the test results, it was found that the double skin composite system has a comparable performance compared to that filled with normal concrete in terms of the ultimate resistance and load–deflection behaviour. The analysis based on ACI and Eurocode approaches show that the current formulae are tentatively applicable to predict the resistance of the double skin structures filled with ULCC.